Automation of the data collection function offers a practical way to bring the pace of data collection more closely in line with data processing. Many manual methods, such as keyboard entry, are considered too slow, costly and error prone to satisfy modern criteria. For this reason, bar code automated data collection technology has gained wide acceptance. The automated data collection process has three phases:
1. Print--Automatic identification is the essential first step, accomplished by attaching a bar code label to a part, document, package, personal identification badge or some other item to be tracked. PA1 2. Capture--The data collection phase occurs when a part moves in or out of inventory, a workpiece comes in or out of a given stage in the manufacturing process, or an employee checks in or out of work. These actions are instantly and accurately captured by scanning the bar code label. Scanners can read information far faster than humans can write or type, and they are far more accurate Compared to an average human transcription error rate of one per 300 characters, the automated error rate is in the range of one per 3 million. PA1 3. Connect--Compiling and computer system input occurs when scanned data is compiled into a central point and manipulated into a form appropriate to the data stream of a host computer. The upshot is accurate data automatically captured as each event occurs, thus permitting management decisions based on solid, current information.
One of the difficulties in the "capture" and the "connect" phases of data collection is the transfer of data to the central point. In conventional bar code systems, the data is commonly collected from a hand-held bar code scanner by cabling the scanner to a reading and/or data distribution device. This allows the scanner to be low power and lightweight. A major disadvantage of a cable link is that scanner use is restricted by the cable. In addition, the scanner operator is required to carry the reader and/or data distribution device.
The assignee of the applicant has considered the use of hand-held scanners fitted with radios as an alternate to cabled scanners. This approach also has significant disadvantages. Radios are heavy, power intensive, and limited in range. In addition, some radios require licensing, and those that do not may be subjected to interference with other radios. Furthermore, installing a radio-based data collection system in an existing facility can be prohibitively expensive.
A symbology-reading input device typically uses a sensing beam to read symbology information, such as a bar code, which consists of alternating areas ("bars") having differing characteristics to which the beam is sensitive. The bar code, or other symbology, can be used to store information or commands which are addressed to other devices. During scanning of the symbology, the input device receives and interprets the fluctuations in the returning sensing beam that are caused by the symbology. For example, it is known to read symbology by means of a hand-held wand which makes contact with the surface on which the symbology is printed and reads the symbology by means of a beam of light. It is also known to use a non-contact scanning device to cause a beam of light to scan across an area containing a bar code. The forms of symbology information include punch cards, magnetically encoded data, passive resonators, and transponder data (radio frequency identification or RFID).
More recently, "two-dimensional" bar codes have been employed. Two-dimensional bar codes often do not appear as alternating bars, but instead may include a different symbology format, such as a matrix format. For the purpose of this invention, "bar code" and "bar code information" is intended to include various types of codes and information which are read by symbology-reading input devices. In addition, other scanner devices are capable of reading different types of symbologies, such as magnetic strip codes and transmissions from RFID devices. These types of scanners may also be used with this invention.
A symbology image is an image representation of information, such as, but not limited to, bar codes. An optical scanning device is a device for reading the bar codes, and may be a decoding or a non-decoding scanner.
optical scanners, as input devices, typically transform the reflected scanning beam to an electronic data form for decoding. In one type of system, the electronic data form is then input to the system wherein a symbology-reading input device driver decodes the electronic data form into a form recognizable by a bar code-reading application program operating on the system. While light used for such scanning is usually visible, optical scanners may also use non-visible light.